In a plant’s male reproductive organs, development of pollen takes place in a structure known as the
stamen
microsporangium
anther
tapetum

Microsporangium

Explanation:

Stamen: that's the place where pollen spores create.

Microsporangium: contains the pollen, is a pollen sac.

Anther: is the place where you can find the pollen, at the end of

Tapetum: a layer of nutrition cells covering the anther.

The pollen its created in the stamen then moves to the anther as the flower growth.

The anther has two pollen sacs, those are called microsporangium, and covered by the tapetum.

d is the answer

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