Final answer:
Enron, Lehman Brothers, and Madoff Investment Securities were all involved in massive corporate scandals due to financial malpractices and poor corporate governance. Lehman Brothers' 2008 bankruptcy signaled the start of an economic crisis. This serves as a stark reminder of the risks of inadequate oversight and governance in the financial sector.
Step-by-step explanation:
Enron, Lehman Brothers, and Madoff Investment Securities share a common factor in that all three were involved in significant corporate scandals and financial malpractices leading to their downfalls. Lehman Brothers, a prominent Wall Street financial services firm, went bankrupt in 2008, which was a pivotal event marking the onset of a widespread economic crisis. This bankruptcy was due in part to a lack of corporate governance, specifically, an oversight failure by the Board of Directors leading to excessive risk-taking without proper risk assessment. Similarly, Enron's collapse was due to accounting frauds, while Bernard Madoff's firm fell due to operating a massive pyramid scheme, defrauding investors of billions of dollars.
Answering the original question about the investment banking firm that went bankrupt in 2008, signaling the beginning of a major economic crisis, the answer is Lehman Brothers, making option C correct. The failures of these institutions serve as cautionary tales of what can happen when corporate governance is weak or neglected, and the consequences can be dire for the economy at large.