How do you calculate what the fully diluted shareholding of a VC Fund will be once they invest in a startup?

a$.$

You take the pre$-$money valuation $($A$),$ add the investment amount $($B$),$ and add the ESOP value $($C$)$ to get D$,$ and then divide B by D$.$

b$.$

You take the post$-$money valuation $($A$),$ add the investment amount $($B$),$ add the ESOP value $($C$)$ to get D$,$ and then divide A$,$ B $+$ C by D$.$

c$.$

You take the post$-$money valuation $($A$),$ add the investment amount $($B$)$ to get C number of shares, and then divide the A $+$ B by C$.$

d$.$

You take the pre$-$money valuation $($A$),$ add the investment amount $($B$)$ to get C number of shares, and then divide the A $+$ B by C$.$