Using data from the table above, select the best explanation for why that cell will be able to eliminate waste most efficiently? \

The correct option is this: CELL 2 WILL THE ONE THAT WILL BE ABLE TO ELIMINATE WASTES MOST EFFICIENTLY. This is because it has the highest surface area to volume ratio which facilitates the exchange of materials between a cell and its environment.
The rate of diffusion of materials into and out of the cell depends on the surface area to volume ratio of the cell. The higher this ratio, the higher the rate of diffusion.

2% of the progeny will be double crossovers for the trihybrid test cross

Explanation:  

By knowing the positions of genes, we can estimate the distances in MU between them per region.

Genes A and B are 10 map units apart (Region I)Genes B and C are 20 map units apart (Region II)Genes A and C are 30 map units apart

A10MUB20MUC---

             Region I                      Region II  

We can estimate the recombination frequencies by dividing each distance by 100.

•recombination frequency of A-B region = 10MU / 100 = 0.10

•recombination frequency of B-C region = 20MU / 100 = 0.20

Now that we know the recombination frequencies in each region, we can calculate the expected double recombinant frequency, EDRF, like this:

EDRF = recombination frequency in region I x recombination frequency in region II.

EDRF = 0.10 x 0.20 = 0.02        

2% of the progeny will be double crossovers for the trihybrid test cross