The direction that an induced current flows in a circuit is given by

Lenz's law

Explanation:

it  states that induced emf  of  different polarities induces a current whose magnetic field opposes the change in magnetic flux through the coil  in order to ensure that original flux is maintained through the coil  when current flows in it.

according to Faraday' s law of electromagnetic induction

Where -ve sign due to lenz's law

Emf is the induced voltage also known as electromotive force

N is the number of loops.

dϕ Change in magnetic flux.

dt Change in time.

wavelength variability is the right one

answer; /// the above statement is (true);