Which event belongs in the missing box in the timeline above?

Which of the following regions has what is considered the most rugged terrain in oklahoma? a. the wichita mountains b. the arbuckle mountains c. the sandstone hills d. the ouachita mountains

1) name any two states which are leading producer of cotton textile in india 2) wht information technology 3) name any two countries which are leading producers of cotton of cotton textile 4) wht is add to pig iron to convert it into steel

Can someone me? i need to have this done as soon as possible! i'm putting 20 points on this!