The Bengal famine was indeed at least partly man made, but the men who made it were the Japanese and German dictators who were trying to take over the world. Lest we forget the Japanese were attacking India at the time, as well as interdicting shipping routes, and had occupied the regions that would normally have been able to export food to Bengal to relieve famine. Britain meanwhile was being bombed on a daily basis and was fighting for its own survival. It is absurd and offensive to the British to blame them for a famine worsened by a war they didn't start, and which if they had lost would have certainly led to far worse catastrophes in India.
Presumably, since you are defending the actions of the British, you don't actually have any skin in the game - you're not like, a Bengali, who's grandparents starved as children. So I'm curious - why are you so strident? It's obviously not 'absurd' or 'offensive', from a cursory glance at the facts, to conclude that this is an anthropogenic famine.
If you want to argue against the preponderance of obvious facts, you have to do a bit more work, and start with the recognition that you're departing from the normal and prima facie understanding of what has occurred. You can't just try and browbeat people into counterintuitive conclusions with a mass of forceful and cherrypicked assertions.
One sign that famines are man-made is if the nation involved is a net food exporter for the duration, regardless of historical frequency and/or natural conditions, because then it's basically unarguable that policy decisions are being made that are leading to starvation: the Great Famine in Ireland is the most common example of this, even though it's contemporary to the potato blight.