Consider the following statements regarding gymnosperms
(A) In gymnospers, the male and female gametophytes have an independent existence
(B) The multicellular female gametophyte is retained within the megasporangium
(C) The gymnosperms are heterosporous
Of these statements.

Options

A. a) (A) and (B) are true but (C) is false
B. b) (A) and (C) are true but (B) is false
C. c) (B) and (C) are false but (A) is true
D. d) (B) and (C) are true but (A) is false

Answer

To solve the question regarding gymnosperms, we need to evaluate the truthfulness of each statement provided:

1. **Statement A**: "In gymnosperms, the male and female gametophytes have an independent existence."
- This statement is **false**. In gymnosperms, the male gametophyte (pollen grain) does not have an independent existence; it germinates and develops within the ovule, which is part of the female reproductive structure.

2. **Statement B**: "The multicellular female gametophyte is retained within the megasporangium."
- This statement is **true**. In gymnosperms, the female gametophyte develops within the megasporangium (ovule) and is retained there, which is a characteristic of gymnosperm reproduction.

3. **Statement C**: "The gymnosperms are heterosporous."
- This statement is **true**. Gymnosperms produce two types of spores: microspores (which develop into male gametophytes) and megaspores (which develop into female gametophytes), making them heterosporous.

Now, let's summarize the evaluations:
- Statement A: False
- Statement B: True
- Statement C: True

Based on the evaluations:
- A is false, and B and C are true. Therefore, the correct option is **D**: "B and C are true but A is false."