Which type of FB ads are more converting

So , after seeing a lots of failure i am still trying out different thing to get my luck work on IM. and this time i am going with promoting my product selling website in FB..

When i was finalizing my ad i saw a option i was not aware of . There were 4 types of ad to be displayed
1) first is a single static image
2) carousel slide show type images
3) And one is video ..

So according to you guys which type of ad has a good converstion ratio… I thought video will be good option to go…

Which type of FB ads are more converting