Which command invalidates the index?

Which command invalidates the index?
A . bin/magento indexerreindex <index_name>
B. bin/magento indexer:reset <index_name>
C. bin/magento Indexerinvalldate <lndex_name>

Answer: B

Explanation:

The command bin/magento indexer:reset <index_name> sets the status of the specified index to “Invalid”. This means that the index needs to be updated before it can be used by Magento1.