How does a line conditioning UPS protect network equipment?

a.

It reduces fluctuations in incoming voltage.

b.

It shields equipment from lightning damage.

c.

It filters line noise from incoming power.

d.

It protects against electrical surges.

c. It filters line noise form incoming power.

Explanation:

Uninterrupted Power Supply (UPS) provide power line conditioning in which they keep the output adjusted to keep it consistent if the input is too high or too low.

UPS also provides protection against electrical surges but the line conditioning protects from the noise. When the input is not consistent it may damage the network equipments so UPS also provides protection from that.