Mutation is the sudden inheritable genetic change that occurs in an organism's DNA sequence. It is a process by which the genetic information of an organism is altered, resulting in a change in the traits of the organism. Mutations can occur spontaneously or can be induced by various factors such as radiation, chemicals, and viruses.

Types of Mutations:
1. Point Mutation - It occurs due to the substitution of one nucleotide with another. It can be of three types:
a. Silent Mutation - The change in nucleotide does not result in any change in the amino acid sequence.
b. Missense Mutation - The change in nucleotide results in the change of one amino acid in the protein sequence.
c. Nonsense Mutation - The change in nucleotide results in the formation of a stop codon, leading to premature termination of protein synthesis.

2. Frameshift Mutation - It occurs due to the insertion or deletion of one or more nucleotides, which changes the reading frame of the codons.

Importance of Mutations:
1. Evolution - Mutations are the driving force behind evolution as they provide genetic variation in a population.
2. Disease - Mutations can also lead to the development of various genetic diseases.
3. Biotechnology - Mutations are used in biotechnology to produce genetically modified organisms (GMOs) and to manipulate genes.

Conclusion:
Mutation is a natural process that occurs in all living organisms. It provides genetic variation in a population, which is essential for the survival and adaptation of organisms to changing environmental conditions. However, mutations can also lead to the development of genetic diseases, and their effects can be harmful or beneficial depending on the context.

The sudden and heritable change in the genetic make up of an individual is called mutation.... Thus, option A is right ans..