Which of the following is regarded as the oldest joint stock bank established in India?

Introduction / Context:
Banking history is a frequent topic in competitive exams and interviews for banking and finance roles. Joint stock banks are banks owned by shareholders whose liability is limited to their share capital. The question asks which among the listed banks is regarded as the oldest joint stock bank in India, testing your knowledge of banking chronology rather than operational details.

Given Data / Assumptions:

• Four well known banks are listed as options: Patiala Bank, Punjab National Bank, Bank of India and Allahabad Bank.
• The question refers specifically to joint stock banks, not to central banks or presidency banks.
• We are concerned with which bank was established earliest in time.
• Standard historical accounts of Indian banking are assumed.

Concept / Approach:
Allahabad Bank, established in the nineteenth century, is often cited in exam oriented material as the oldest joint stock bank in India. Punjab National Bank and Bank of India were founded later, in the late nineteenth and early twentieth centuries respectively. Patiala Bank also dates from a later period. Therefore, to answer the question we identify which bank is historically recognized as the earliest joint stock bank and select that option.

Step-by-Step Solution:
Step 1: Recall that Allahabad Bank is widely mentioned in banking history as one of the earliest Indian joint stock banks. Step 2: Compare its founding period with Punjab National Bank and Bank of India, which were founded later. Step 3: Note that Patiala Bank is also a later entrant and not usually named as the oldest joint stock bank. Step 4: Eliminate options A, B and C based on the relative founding dates and historical references. Step 5: Conclude that option D, Allahabad Bank, is the correct answer.

Verification / Alternative check:
You can verify by recalling common facts repeated in study guides. Many textbooks and coaching notes state that Allahabad Bank is the oldest joint stock bank in India among Indian owned banks. While there were earlier banks in the country, including presidency banks and foreign controlled banks, the question targets the specific category of joint stock banks. Since none of the other listed banks are historically cited as the oldest in this category, this confirms Allahabad Bank as the correct answer.

Why Other Options Are Wrong:
Option A, Patiala Bank, is not usually recognized as the earliest joint stock bank and came into existence later. Option B, Punjab National Bank, is a major nationalized bank established after Allahabad Bank and so cannot be the oldest among the four. Option C, Bank of India, was also founded later and is known for other distinctions, not for being the earliest joint stock bank. These options may be prominent banks but they do not match the specific historical milestone asked in the question.

Common Pitfalls:
Students often confuse oldest bank in India with oldest joint stock bank, or they mix up presidency banks, central bank and modern commercial banks. Another pitfall is to choose more familiar names like Punjab National Bank or Bank of India simply because they are widely known today. To avoid these errors, it is helpful to memorize a short list of historical milestones such as the earliest joint stock bank, the nationalization year and key mergers.

Final Answer:
The bank regarded as the oldest joint stock bank established in India is Allahabad Bank.