When Protostars Are FIRST Formed from the Interstellar Medium,they Are

Multiple Choice

When protostars are FIRST formed from the interstellar medium,they are usually

A) detected easily because their light ionizes the surrounding interstellar gas,forming H II regions.
B) very bright in ultraviolet light due to numerous flares (like solar flares but hotter and brighter) .
C) hidden from sight by dust clouds that emit infrared radiation.
D) detected by emission lines in their visible spectra,emitted by gas being blown off their surfaces into space.