I'm confused. You wrote down:

Decreased COL → More CLD → Profits Increase → Congestion Decrease

But doesn't the last sentence add a CONJUNCTION clause to the mix? Meaning that profits can't increase unless BOTH cost of living decreases and congestion decreases?

B might not necessarily be right considering that Cost of Living decreases do lead to Consumers living there to increase, which could lead to more Traffic Congestion meaning that Profits might not increase. Of course, we can't assume that traffic congestion will increase but that is one example where just because cost of living decreased, the profits of businesses wouldn't increase.

For Q2: I got KIW and ERP and BFAW->ASP

Why could that not also be true?

Why even switch AND to OR? Doesn't the contrapositive also work if you say that "If you don't have A AND you don't have B, you can't have C"?