Capturing the bishop is logical, but White gains good central control with the pawns on c4 and e4. It's hard to judge who benefits. Alternatively, Black can develop the bishop to c5, leading to play typical of the Italian opening, or play 4...Bb4 and maybe ...d7-d5 next.
1. e2e4  1... e7e5  2. f1c4  2... g8f6  3. d2d3  3... b8c6  4. b1c3 