I think you would be using a topographic Map, So the answer should be A
Answer:

Explanation:
wavelength, λ = 2.5 m
speed, v = 13.8 m/s
Amplitude, A = 0.14 m
The general equation of the transverse harmonic wave which is travelling right is given by

where, Ф is phase
At t = 0, x = 0 , y = 0.14 m
0.14 = 0.14 Sin Ф
Ф = π/2
So, the equation is


This process shows alpha decay so X represents an alpha particle. The characteristic of alpha decay is that the mass number stays constant while the proton number increases.