"which of these is a tropic hormone secreted by the anterior pituitary gland

Tropic hormone are produced by the anterior pituitary gland and are hormones that control the activities of other endocrine glands. The anterior pituitary gland relies on regulatory hormones that come from the hypothalamus to tell it when to make and secrete its own hormones.

it's c. (to reduce the greenhouse effect/carbon gasses)

before, trains worked using the steam engine. thus, it uses heat so it is crucial to apply heat balance. the steam engine absorbs energy during the stage of boiling water. so, this is the endothermic reaction. when the steam is used to work the piston, it has to release this energy through running the train. the excess energy is released as an exhaust to the chimney. this is the exothermic process because it releases energy to the surroundings.