Find the Probability for the Experiment of Tossing a Coin $\frac { 1 } { 2 }$

Multiple Choice

Find the probability for the experiment of tossing a coin two times.Use the sample space
S = {HH,HT,TH,TT}

The probability of getting exactly two tails.

A) $\frac { 1 } { 2 }$
B) $\frac { 1 } { 4 }$
C) $\frac { 3 } { 8 }$
D) $\frac { 1 } { 3 }$
E) $\frac { 1 } { 8 }$