Which natural boundary shielded the Indus and Ganges Valleys from invaders to the north?

Mountain Ranges.

Explanation:

The natural boundary which shielded the Indus and Ganges Valleys from invaders to the north was mountain ranges. The world's tallest mountains that stood on the north of the Indua valley served as a guard to protect the Indus and Ganges valley from being invaded.

Indus Valley is surrounded by the world's tallest mountain range of the Hindu Kush, the Karakorum, and the Himalayas in the north. Indus and Ganges valley form the most fertile landforms.

Thus the correct answer is that the natural boundary of mountain ranges guarded Indus and Ganges Valley from being invaded.

absolute poverty the condition of having too little income to buy the necessities-- food, shelter, clothing, health care.

achieved status a social position (status) obtained through an individual's own talents and efforts.

affirmative action the requirement that employers make special efforts to recruits hire and promote qualified members of previously excluded groups including women and minorities.

aggregate a collection of unrelated people who do not know one another but who may occupy a common space--for example, a crowd of people crossing a city street.

agrarian societies societies in which large scale cultivation using plows and draft animals is the primary means of subsistence.

alienation the separation or estrangement of individuals from themselves and from others.

amalgamation the biological as well as cultural assimilation (merging) of racial or ethnic groups.

anomalies in science observations or problems that cannot be explained or solved in terms of a prevailing paradigm.

anomie a breakdown or confusion in the norms, values, and culture of a group or a society. a condition of relative normlessness.

anomie theory the theory suggesting that deviance and crime occur when there is an acute gap between cultural norms and goals and the socially structured opportunities for individuals to achieve those goals.

anticipatory socialization the process of taking on the attitudes values and behaviors of a status or role one expects to occupy in the future.

apartheid the recent policy of racial separation in south africa enforced by leg

explanation:

you should try adrenaline. it kicks in in situations like this.