Question

stars are classified according to temperature using which system of letters (from hottest to coolest)? a o, b, a, f, k, g, m b b, o, a, f, g, k, m c m, o, p, l, g, a, f d o, b, a, f, g, k, m

Explanation:

The Morgan - Keenan spectral classification system orders stars by temperature from hottest to coolest as O, B, A, F, G, K, M.

Answer:

A. O, B, A, F, K, G, M