Atype o star is likely to appear yellow blue green red

Blue,

Explanation:

The O type of star is generally found in the hot blue-white star and has a temperature that exceeds 30,000 K. They have a strong absorption line of ionized helium. This star is particularly rare type and 0.00002% of all the O stars. These stars are generally very bright thus end their lives more quickly int the supernova explosions. They emit UV lights and are more dynamic.

Maybe a horizontal because its a pattern