How did Bohr's atomic model explain the fact that the atomic emission spectrum of an element consists of fine lines of only certain colors?

i think it is d. e because the next one is igneous.

> b takes place in the gas phase in an isothermal tubular reactor. the feed is one mole of a per one mole of c, an inert. the entering temperature and pressure are 427°c and 10 atm, respectively. the gas constant r = 0.08206 atm · l/mol · k.