How do conglomerates and vertical mergers differ from horizontal mergers? they increase

The correct option is D
They do not usually lessen competition in the marketplace.
Vertical and conglomerate mergers do not usually lessen competition in the market. This is because conglomerate and vertical involves merging of unrelated product firms. With horizontal mergers however, merging involves firms producing similar products thus lessening competition.

By 1786, Americans recognized that the Articles of Confederation, the foundation document for the new United States adopted in 1777, had to be substantially modified.  The Articles gave Congress virtually no power to regulate domestic affairs--no power to tax, no power to regulate commerce.  Without coercive power, Congress had to depend on financial contributions from the states, and they often time turned down requests.  Congress had neither the money to pay soldiers for their service in the Revolutionary War or to repay foreign loans granted to support the war effort.  In 1786, the United States was bankrupt.  Moreover, the young nation faced many other challenges and threats.  States engaged in an endless war of economic discrimination against commerce from other states.  Southern states battled northern states for economic advantage.  The country was ill-equipped to fight a war--and other nations wondered whether treaties with the United States were worth the paper they were written on.  On top of all else, Americans suffered from injured pride, as European nations dismissed the United States as "a third-rate republic."

America's creditor class had other worries.  In Rhode Island (called by elites "Rogue Island"), a state legislature dominated by the debtor class passed legislation essentially forgiving all debts as it considered a measure that would redistribute property every thirteen years.  The final straw for many came in western Massachusetts where angry farmers, led by Daniel Shays, took up arms and engaged in active rebellion in an effort to gain debt relief.

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