Answer:
<em><u> The expression is, B)</u></em>
Step-by-step explanation:
<em>Since, the sum of an A.P. is,</em>
<em>Where, n is the number of terms,</em>
<em>a is the first term of the A.P. ,</em>
<em> is the last term of the A.P. ,</em>
<em>Here, we have given,</em>
<em>a = 102, = 159, and n = 20,</em>
<em>Thus, the sum of the given A.P. is,</em>
<em>Which is the required expression.</em>