When a corporation sells all or substantially all of its assets to another corporation, generally,
a. a majority of both shareholders and directors must approve.
b. one-third of the shareholders must approve.
c. fifty-one percent of the directors must approve.
d. two-thirds of the directors must approve.

a. a majority of both shareholders and directors must approve.

Explanation:

Whenever a corporation decides to dispose off all of it's assets or substantially all of it's assets to another corporation, following points are noteworthy

The Board of directors first have to propose a resolution regarding disposition which has to be approved Secondly post approval of the said resolution, the act of "disposition" also requires approval by the corporation's shareholders.Such approval must be obtained by majority of the votes cast in it's favor.

In short, disposition of all or substantially all the assets requires an approval of a majority of both shareholders and directors.

The business cycle is the periodic but irregular up-and-down movement in economic activity, measured by fluctuations in real gross domestic product (gdp) and other macroeconomic variables. a business cycle is typically characterized by four phases—recession, recovery, growth, and decline—that repeat themselves over time. economists note, however, that complete business cycles vary in length. the duration of business cycles can be anywhere from about two to twelve years, with most cycles averaging six years in length. some business analysts use the business cycle model and terminology to study and explain fluctuations in business inventory and other individual elements of corporate operations. but the term "business cycle" is still primarily associated with larger (industry-wide, regional, national, or even international) business trends.