To stretch a function by a factor of 3, we multiply the function by 3. This eliminates A and D.
To translate a function 4 units right, we add -4 to the variable before anything else is applied to it; this eliminates C.
In choice B, the log function is multiplied by 3, which gives us our vertical stretch; and the x is subtracted by 4 before anything else is applied to it, so it is translated 4 units right.</span></span>