Sec 44ad

For AY 2014-15,Retail Trading Business(Proprietor)
Turnover : Rs. 70 lakhs
Net profit : less than 8%
Also maintain books of account u/s 44aa.

now, my queries are as follow...

1) is it compulsory to opt. Sec 44AD ?
   if no than audit u/s 44AB is compulsory ?
   as in sec.44AD read like
   " Person covered u/s 44AD "

So, assessee has not opt sec 44AD and maintain books of account u/s 44AA...what will ur ans for Audit U/s 44AB