The function g(x) is a mirror image of the function f(x), which means that f(x) was reflected over the y-axis. To do so, you have to invert the sign of the x-term of the function, symbolically:

The curve of the function is less pronounced, which indicates that the function f(x) was compressed horizontally, to do so, you have to multiply the x-term of the function by a constant with a value less than 1.
For example 1/2, then:

The correct option is A