Questions

The required English word is SPARED.

It has SPA, SPARE, ARE, RED, SPAR, PARED, PA, PAR, RE, PARE.

Data registers - can be assigned to a variety of functions by the programmer. They can be used with any machine instruction that performs operations on data.
Address registers - contain main memory addresses of data and instructions or they contain a portion of the address that is used in the calculation of the complete addresses.

From the history,

The Erie Canal was completed in 1800's

The signing of the Declaration of Independence in 1776 and after that the American Revolution was started in the same 1776.

The Iroquios Confederacy was formed early when the Europeans first began comonizing, may be early in 1600's.

So, from the above data of history, Iroquois tribes formed the Iroquois Confederacy was the event that occured first among the options.