Tejal, This is a rather nice set of images.
I think for me that the middle image works best. I quite like the contrast between the active swimmer and the other who is floating nearby. It creates a pleasing dynamic aspect, enhanced for me by the additional contrast created by the dark area at the top of the image.
Comparing the bottom image with the one above I think there is too much 'open' water between thewo swimmers and it results in a distracting 'split' in the image. I have a feeling that there are two separate compositions competing against each other here.
The top image is similar to the middle capture but for me, but does not work as well. Again it is just my own preference but I think it would benefit from a crop top and bottom to place a bit more focus on the floating gentleman.
I do really like the way you have handled the light in these shots, the contrasts are spot on for me.