Dicot seeds are the seeds that belong to the class of flowering plants known as dicotyledons or dicots. These plants have two embryonic leaves or cotyledons inside their seeds. Let's examine each option and determine which one is a dicot seed.

a) Gram (Correct answer)
- Gram seeds are dicot seeds.
- They have two cotyledons inside the seed.
- Gram belongs to the family Fabaceae and is commonly known as chickpea or Bengal gram.

b) Maize
- Maize seeds are monocot seeds.
- They have a single cotyledon inside the seed.
- Maize belongs to the family Poaceae and is commonly known as corn.

c) Wheat
- Wheat seeds are monocot seeds.
- They have a single cotyledon inside the seed.
- Wheat belongs to the family Poaceae and is a cereal grain.

d) Rice
- Rice seeds are monocot seeds.
- They have a single cotyledon inside the seed.
- Rice belongs to the family Poaceae and is a staple food crop.

e) None of these
- This option is incorrect as gram seeds are dicot seeds.

In conclusion, among the given options, the dicot seed is gram (option A). Gram seeds have two cotyledons inside the seed, distinguishing them from the monocot seeds of maize, wheat, and rice which have a single cotyledon.