Asserion: When a beetle moves along the sand within a few tens of centimeters of a sand scorpion, the scorpion immedeately turn towards the beetle and dashes to it.
Reason: When a beetle disturbs the sand, it sends pulses along the sand surface one set of pulses in londitudinal while other set is transvers.

Options

A. if both the assertion and reason are true and reson is a true explanation of the assertion.
B. if both the assertion and reason are true but the reason is not the correct explanation of assertion.
C. If the assertion is true but reason is false.
D. If both the assertion and reason are false.

Answer

A

Explanation

A beetle motion sends fast longitudenal pulses and slower transvers waves along the sand surface. The sand scorpion first intercepts the longitudinal pulses and learns the direction of the beetle, it is in the direction of which ever leg is disturbed earliest by the pulses. The scorpion then senses the time interval `(Delta t)` between that first interception and the interception of slower transverse waves and uses it to determine the distance of the beetle. The distance is given by
`Delta t=(d)/(v_t)-(d)/(v_l)`