4 question. With correct explanation..:

4. Development of male gametophyte is.
(a) in vivo                        (b) in situ
(c) both (a) and (b)          (d) None of the above.

Dear student
Please find below the solution to the asked query
 

The correct option is c.

In case of flowering plants, the male gametophyte also called pollen grain develops within the microsporangium/pollen sacs of anther. It's development is in vivo means occurring within plant body (here anther of a flower) and also in situ means within the original location i.e microsporangium. 

 
Hope this information will clear your doubts about the topic.
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