Why did the military restore democratic rule in argentina?

The Military in Argentina for decades held sway over the political life in the country. With the support of the United States, they grew stronger and began to restrict civil liberties in the country.

With time, this gave rise to disfranchised population which demanded more rights. The period also gave rise to several communist factions and rebels who continuously fought the military government.

The army continued with a 'semi-democratic' government which was seen as faux democracy.

By the end of the 80s and 90s, the Army had lost support of the major population of the country which gradually gave rise to a new political class which moved towards democracy.

The answer would be a