How can calculations affect the accuracy and precision of experimental results?

Question

Calculations, such as division and addition, can decrease precision in data by generating more digits that can be significant.

Nonzero digits are always significant; however, when making calculations, a zero may be computed.

Exact values have more significant figures than any other value; thus, when making calculations, the computed amounts are not precise.

Calculations, such as division and addition, can increase precision in data by generating more digits that can be significant.

B?