I think that the question is about 1990s specifically (in 1900 it was not independent, but part of the Austrian Empire) and the country is Czechoslovakia.
It split into Czech Republic (now also called Czechia, also officially) and into Slovakia: today two independent countries and part of the EU
The answer that fits the blank is ECOLOGICAL CHANGE. Ecological change refers to any changes, whether good or bad, that either harms or improves the environment and balance. There are different types of people within the community and these people work together to bring change. Once changes happen, this also brings changes to the environment.
Americans began to rethink the nation's environmental policies partly as a result of the oil embargo.
When the members of the Organization of Arab Petroleum Exporting Countries, led by Saudi Arabia, declared an oil embargo in October 1973, the 1973 oil crisis—also known as the first oil crisis—began. Targets of the embargo were countries that had backed Israel during the Yom Kippur War. Moreover, they also imposed an embargo on the US in retaliation for its decision to resupply the Israeli military and to use this as leverage in the peace talks following the war. The 1979 oil crisis, also referred to as the Second Oil Crisis or the 1979 Oil Shock, was an energy crisis brought on by a decline in oil production following the Iranian Revolution.
More about the environment brainly.com/question/1888324
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Here are very high levels of mobility (nomadism), but very little migration. Stage two (“Early transitional society”): During stage two a “massive movement from the countryside to cities" occurs. ... Then the net-out migration trend shifts to a net-in migration trend as more people immigrate than emigrate.
Migration trend follow demographic transition stages. People become increasingly mobile as industrialization develops. More international migration is seen in stage 2 as migrants search for more space and opportunities already in stages 3 and 4. Stage- 4 countries show less emigration and more intraregional migration.
The correct answer is b.
Of course, consuming alcohol leads to lowered inhibitions, which means that people are more likely to make "stupid" decisions and take risks, for example in relation to sex. At the same time, college students can also be swayed to take risks due to factors like raging hormones and peer pressure.