Nifty Bank Option strategy for Next week expiry

Nifty Bank has breached the 20 EMA line and retested it yesterday, If it sustains below it then next support is at 50 EMA @ 17730 levels. I decided to short OTM 18300 CE @ 17.90 and 17200 PE @ 15.30.
I expect Nifty Bank to move in range between 18000 and 17700 levels making both this option to depreciate its value.