1. The problem asks to identify the graph transformation of the function $g(x) = e^{x+1}$ from the graph of $f(x) = e^x$. 2. The general rule for horizontal shifts in functions is: if $g(x) = f(x + c)$, the graph of $f(x)$ shifts horizontally by $-c$ units. 3. Here, $g(x) = e^{x+1} = f(x+1)$, so $c = 1$. 4. Applying the rule, the graph shifts horizontally by $-1$ units, which means 1 unit to the left. 5. Therefore, the correct transformation is a horizontal shift left by 1 unit. Final answer: B. horizontally left 1 unit