What were some of the key differences among the colonies of british north america around 1860

What prevented the success of mao zedongs great leap forward? a- the people focused too much on tending their farms and not on industry. b- the goods being made were fewer and lower quality than expected. c- too little house in existed for everyone who wanted to live in communes. d- industry and mining operations in the cities required too many people. (the right answer will get brainliest)