Which Star Spends the Longest Time as a Main-Sequence Star $\odot$

Which star spends the longest time as a main-sequence star?

A) 0.5 M _$\odot$
B) 1 M _$\odot$
C) 3 M _$\odot$
D) 6 M _$\odot$
E) 10 M _$\odot$