As per KVPY eligibility criteria, A candidate is eligible to apply for KVPY after 12th if he is enrolled in an UG program in basic science with the continuous study. There should not be any gap between the 12th class and 1st year of UG. So you are not eligible to apply for KVPY 2019 exam.
Hope it answers your query!!!
Sorry to inform but no droppers are allowed to appear for the KVPY examination.
You may apply for it if you are enrolled in the 1st year of your Undergraduate Course in Basic Science from some registered college under the name of SB Stream.
Hope this helps.
All the Best !
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