This is an "except" style question, three of the four names were real Padma award recipients in 2015 and one was not.
Kharag Singh Valdiya: this name is linked to a real 2015 Padma awardee, a noted earth scientist honoured for work in geology, so this is not the exception.
Mohammad Yusuf Khan: this is the birth name of veteran actor Dilip Kumar, who received the Padma Vibhushan in the 2015 list, so this is also not the exception.
Lakshmi Gopala Naidu: correct, this name does not match any of the actual 2015 Padma awardees, making it the odd one out that the question is asking for.
Saichiro Misumi: this is a real name from the 2015 list, a foreign national honoured for his contribution, so this is not the exception either.
So option C, Lakshmi Gopala Naidu, is the name that was not actually conferred a Padma Award in 2015.