IGIDR - MACRO

[MomoChan]

I marked (3) but the answer scheme says (2).
Please help withe explaination of why (b) is true and (a) is not .

[get.the.lens.right]

When Money Supply increases the interest rate should fall >> Positive effect on Investment. Therefore a cannot be an option.
As for b, higher investment leads to higher output and employment hence (due to high unemployment).
Hence b and c >> Option (2)