<u>Answer:</u> A. constant
Without any air resistance, as the golf ball falls into the well, its speed is constant.
<u>Explanation:</u>
Given that when the ball is released,<em>there is no air resistance acting on ball. So the ball is freely falling.
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The only force acting on the freely falling body is the gravitational force pulling the body towards the centre of the earth.Here the only acceleration acting on the body is the <em>acceleration due to gravity.</em>
The acceleration due to gravity is . so through out the journey of the ball,the acceleration is . <em>So as the acceleration is constant, the speed is also constant.</em>