Hi singhprerna - welcome to GMAT Club!
It's a little hard to give advice without knowing a lot more about you but just based on what you've stated, we can offer the response that an MBA is very much a practical education, and the adcoms look to see how you're prepared for a specific post-MBA career path. Since you know you want to move to the client side, then anything you can do in your career now to position you for that would be helpful - meaning, transferable skills and relevant experience that makes you better-qualified for that type of work in future. You don't have to facilitate that big jump pre-MBA but you do want to show how you have a good foundation that you can leverage with your studies and to help you gain your first job after bschool.
Research roles typically don't do that, though there are exceptions. What you should do is evaluate your opportunities based on which will bring you closer to that future goal of working in marketing (for a CPG company or whatever).
Hope this helps! If we've fully misunderstood your situation and what you're asking about, please don't hesitate to write back and we'll try again.
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