G

Let CP = 16k
so SP = 20k (25% profit)
ATQ, this is gained after 20% commission. Hence MP (retail price) = (100/80)*20k = 25k
Now, after Increasing commission to 24% from the same 25k we still have 76% left with us which is our selling price.
so new SP = (76/100)*25k = 19k.
Hence profit is 3k and profit %age is (3/16)*100 = 18.75%

Note k=*1000 here

14%