Is it better to consume a multivitamin tonic in liquid form or multivitamin in tablet form?

Either: both are well absorbed unless some other issue. Check content of vitamins on label.

I like capsules too: I have heard those who sell liquid vitamins claim tablets are poorly absorbed but well-formulated tablets are well-absorbed so it is a matter of personal preference. But also consider vitamins in capsule form, which tend to be easier to swallow than pills and on average may be even better absorbed than tablets.