Your answer for this question is the third option.
When a wire is moved inside uniform magnetic field then its free electrons will experience magnetic force on it due to which wire will have potential difference at its ends.
Now here we will have magnetic field due to earth and wire is moving in this constant field so induced emf is given by formula

given that



now by using the above formula we will have



<span>The atomic number of
a neutral atom is equal to the number of protons and the number of electrons of
the atom. The atomic weight meanwhile is equal to the sum of the number of
protons and number of neutrons. In this case, the atomic number of the atom is 3 and the atomic mass is 7. Hence the element is Lithium, a metal </span>