A Naturally Occurring Element Consists of Three Isotopes

A naturally occurring element consists of three isotopes. The data for the isotopes are:
Isotope 1: 146.9672 u, 64.792%
Isotope 2: 148.9638 u, 26.117%
Isotope 3: 149.9592 u, 9.0910% What is the average atomic mass of this naturally occurring element?

A) 49.254 u
B) 147.76 u
C) 148.63 u
D) 148.67 u
E) 147.88 u