It seems you forgot your options, but here are some things found in a chloroplast:
grana
Granal thylakoids
Stroma
Nukleloids (DNA rings)
Ribosomes
Starch granules
membranes
Now, some examples of thing NOT found in a chloroplast:
Endoplasmic Reticulum (that's another organelle)
Answer:
this represents response to the environment
a neurosecretory cell in the hypothalamus.