we have that
using a graph tool
see the attached figure
case A) f(x) = 4^x
this function is not represented in the graph
case B) f(x) = 4^(x) − 3
this function is not represented in the graph
case C) f(x) = 4^(x) + 3
this function is represented in the graph
case D) f(x) = 4^(x + 3)
this function is not represented in the graph
the answer is
case C) f(x) = 4^(x) + 3