How is capital gains from sale of listed bonds taxed in India?

Bonds in question:
INE092T08CD4 IDFC FIRST BANK LIMITED TRANCHE-1 SR-II NCD 12NV20 FVRS5000

An Indian resident purchased these bonds in fy2010 and sold them in fy2019 – a year before maturity – and thereby incurs long term capital gains. As per my understanding, no indexation (of purchase price) is allowed in this case. At what rate are the gains taxable?

Schedule CG of the ITR2 excel utility seems to have two different sections to report this:

B2. From sale of bonds or debenture (other than capital indexed bonds issued by Government)

B3. From sale of, (i) listed securities (other than a unit) or zero coupon bonds where proviso under section 112(1) is applicable

B2 seems to be taxable at 20% without indexation and B3 at 10% without indexation.

Which one is applicable in the above case?