Find the highest common factor of 36 and 84.  Choose the correct choice from the following options.
A) 4  B) 6  C) 12  D) 18  E) 19
36 = 22 x 32   84 = 22 x 3 x 7   H.C.F. = 22 x 3 = 12.   Answer: Option 12
<result>C</result>
Find the highest common factor of 36 and 84.