When hitler sent troops into the rhineland in 1936 and austria in 1938, other european nations responded with immediate armed resistance. united to protect czechoslovakia. offered no resistance. convened the munich conference.

When Hitler started his invasions over Europe in Rhineland and Austria, the other European nations didn't offer any resistance.

Specifically respecting the Rhineland, part of the British public opinion considered that the Germans only "recovered their backyard" when stationing troops in the Rhineland and it was not convenient to reproach them for this violation of an international treaty, maintaining a policy of appeasement to keep the relations with the III Reich in good condition, a position supported then by British Foreign Minister Anthony Eden.

Faced with this British indecision, the French did not feel sufficiently supported for a far-reaching military action and let the remilitarization of the Rhineland conclude unhindered; such a denouement caused the surprise of the Wehrmacht commanders and further increased the prestige of Adolf Hitler over the professional military.

About the Invasion of Austria of 1938, the international response to it was quite lukewarm: theFirst World War allies only presented diplomatic protests, without taking concrete actions to reverse the situation, even though they were, as specifically established by the Treaty of Versailles, those responsible for prevent political union between Austria and Germany. The United Kingdom argued that the events of the Invasion of Austria were irreversible, even recognizing that Hitler had violated the peace treaty. France expressed itself in similar terms and refrained from calling for any boycott against Germany for this action.

c.) biotic: snails; abiotic: temperature climate

the answer is b hope that