A, convection, is your answer
We will apply the concept of period in a pendulum, defined as the product between 2
by the square root of the length over gravity, this is mathematically

Here,
T = Period
L = Length
g = Acceleration due to gravity
For the period to be 1 second, then we must look for the necessary length for such a requirement so




The meter's length would be slight less than one-fourth of its current length. Also, the number of significant digits depends only on how precisely we know g, because the time has been defined to be exactly 1s.
Therefore the correct answer is C.
T<span>he phenomenon of </span>static electricity<span> requires a separation of </span>positive<span> and </span>negative<span> charges. When two materials are in contact, electrons may move from one material to the other, which leaves an excess of </span>positive<span>charge on one material, and an equal </span>negative<span> charge on the other.</span>