log(a(a(a)^1/4)^1/4)^1/4 here base is a.  Choose the correct choice from the following answers
A) 0  B) 21/64  C) 1  D) 22/63  E) 23/65
log(a(a(a^1/4)^1/4)^1/4   =&gt; log(a(a^1+1/4)^1/4)^1/4   =&gt; log(a(a^5/4)^1/4)^1/4   =&gt;log(a(a^5/16)^1/4   =&gt;log(a^1+5/16)^1/4   =&gt;log(a^21/16)^1/4   =&gt;log(a^21/64)   =&gt;21/64 log(a)   =&gt;21/64   ANSWER:21/64
<result>B</result>
log(a(a(a)^1/4)^1/4)^1/4 here base is a.