High Order Thinking Skills (HOTs) - 1 - Free MCQ Test with solutions

(i) True – Ice floats because it is less dense than water.
(ii) False – Water boils at 100°C.
(iii) True – Water expands on freezing.
(iv) False – Water is a compound (H₂O).

(i) True
(ii) False – Like poles repel
(iii) True – Each piece becomes a magnet
(iv) False – Opposite poles attract

For electricity to flow, a circuit must be closed, not open. Let’s analyze the statements:

(i) A circuit must be open for electricity to flow: This is incorrect. A circuit must be closed to allow electricity to flow.
(ii) Conductors allow electricity to pass through them: This is correct. Materials like metals are conductors and allow electricity to pass.
(iii) Insulators prevent electricity from passing through: This is correct. Insulators like rubber stop electricity from flowing.
(iv) A switch can open or close a circuit: This is correct. A switch controls the flow of electricity by opening or closing the circuit.

Thus, the only incorrect statement is (i). Therefore, the correct answer is Option B.

Transpiration is the process of water movement through plants, not rivers. Evaporation, condensation, and precipitation are correctly described.

The correct answer is Option B - (iii) and (iv) only

Statement (i) is true because camouflage lets animals blend into their surroundings, making them less likely to be seen by predators.

Statement (ii) is true because mimicry is when an animal looks like another organism to gain an advantage, for example to avoid being eaten.

Statement (iii) is incorrect because hibernation is a period of reduced activity with a lowered body temperature and slower body processes during cold months, not increased activity.

Statement (iv) is incorrect because migration is carried out by many kinds of animals, not only birds; examples include fish, some mammals and insects.

Thus, statements (iii) and (iv) are incorrect.

(i) Water freezes at 0 degrees Celsius: This is correct. Water turns into ice at 0°C.
(ii) The sun is a planet: This is incorrect. The sun is a star, not a planet.
(iii) Plants produce oxygen during photosynthesis: This is correct. Plants release oxygen as a byproduct of photosynthesis.
(iv) The Earth has one moon: This is correct. The Earth is accompanied by a single natural satellite, the Moon.

Thus, the correct statements are (i), (iii), and (iv). Therefore, the correct answer is Option C.

(i) True – Lower pressure → lower boiling point
(ii) True
(iii) True
(iv) False – Humans have 2 lungs

(i) Plants take in carbon dioxide and give out oxygen: This is correct. Plants release oxygen during photosynthesis while absorbing carbon dioxide.
(ii) Metals are poor conductors of electricity: This is incorrect. Metals are good conductors of electricity.
(iii) A lever is a simple machine: This is correct. A lever is a basic tool that helps make work easier.
(iv) The Earth revolves around the moon: This is incorrect. The Earth revolves around the Sun, not the Moon.

Thus, the correct statements are (i) and (iii). Therefore, the correct answer is Option A.

(i) A shadow is formed when light is blocked by an object: This is correct. Shadows are created when an object obstructs the path of light.(ii) Sound cannot travel through a vacuum: This is correct. Sound requires a medium like air, water, or solids to travel and cannot propagate in a vacuum.
(iii) The Earth is the third planet from the sun: This is correct. Earth is the third planet in the solar system, located between Venus and Mars.(iv) Bacteria are visible to the naked eye: This is incorrect. Bacteria are microscopic organisms and can only be seen using a microscope.

Thus, the correct statements are (i), (ii), and (iii). Therefore, the correct answer is Option B.

(i) Leaves are green because of chlorophyll: This is correct. Chlorophyll is the pigment responsible for the green color of leaves.
(ii) Electricity can be generated from sunlight: This is correct. Solar panels convert sunlight into electricity.
(iii) All mammals give birth to young ones.: This is incorrect. Most mammals give birth to live young ones but a few exceptions like the platypus and echidna.
(iv) Water is essential for all known forms of life: This is correct. Water is crucial for the survival of all living organisms.

Thus, the correct statements are (i), (ii), and (iv). Therefore, the correct answer is Option C.