Consider This Structure The Bond Angle Between Bonds C and D Is Approximately

Multiple Choice

Consider this structure:
$$\mathrm { H } _ { 3 } \mathrm { C } \stackrel { a } { - } \mathrm { C } \stackrel { b } { \equiv } \mathrm { C } \stackrel { c } { - } \mathrm { CH } \stackrel { d } { = } \mathrm { CH } \stackrel { e } { - } \mathrm { CH } _ { 2 } \stackrel { f } { - } \mathrm { CH } _ { 3 }$$ The bond angle between bonds c and d is approximately

A) 109.5°.
B) 120°.
C) 60°.
D) 180°