No, mcq in jee mains has only one correct option, unless their is something wrong in that.

As per changed JEE Main exam pattern 2021, each subject will have 20 MCQs (only one option correct) and 10 Numerical Value Questions and out of 10 only 5 have to be done

Hello

In JEE Mains there are only multiple choice questions and not multiple options correct questions (those questions will be asked in JEE Advanced after you clear JEE Mains). Also, in JEE 2021 there will be numerical questions too (which will not carry any negative marking). From 2021 there will be 20 MCQs and 10 numerical questions (out of which you have to do 5 numericals) for each subject, PCM . For more details you can click on https://engineering.careers360.com/articles/jee-main-exam-pattern