D

Step 1: Understand the concept of angle of dip.
The angle of dip (or magnetic inclination) is the angle that a magnetic field makes with the horizontal plane.
Step 2: Know about the components of the Earth's magnetic field.
The Earth's magnetic field can be resolved into two components:
V - vertical component
H - horizontal component.
Step 3: Analyze conditions at the magnetic equator.
At the magnetic equator, the vertical component of the magnetic field (V) becomes zero because the magnetic field lines run horizontally at this location. The horizontal component (H) is at its maximum.
Step 4: Conclude the relationship.
Therefore, at the magnetic equator, since V = 0 and H is maximum, the angle of dip is zero.
Hence, the correct answer is that the value of H is zero.
Therefore, the answer is Option D: The value of H is zero..