A series of country names is given with one member missing. The series is based on an important international economic group. Choose the correct alternative from the given options that will complete the series: Brazil, Russia, ?, China, South Africa.

Introduction / Context:
This reasoning question uses a series of country names: Brazil, Russia, ?, China and South Africa. Rather than forming a random list, these countries are well known as members of a specific international economic grouping. You must identify that grouping and then determine which member country is missing. Questions like this test your general awareness of world affairs and your ability to recognize patterns in real-world categories such as political or economic alliances.

Given Data / Assumptions:

• Given series: Brazil, Russia, ?, China, South Africa.
• Options: India, Indonesia, Iran, Japan.
• We assume the series is not random and is likely connected to a known group of major emerging or influential economies.
• The missing country must fit naturally into the same grouping as the others.

Concept / Approach:
The key idea is to recognize that Brazil, Russia, China and South Africa are all part of the BRICS group, which is an association of major emerging national economies. Historically, BRIC referred to Brazil, Russia, India and China, and the group later expanded to BRICS with the addition of South Africa. Once you recall this acronym and its member countries, it becomes clear which of the given options completes the set. This question therefore relies mainly on general knowledge rather than on letter-level or numerical patterns.

Step-by-Step Solution:
Step 1: Examine the known terms: Brazil, Russia, China and South Africa. These four countries are widely recognised as members of the BRICS group. Step 2: Recall that the original BRIC grouping represented Brazil, Russia, India and China. South Africa was later added to form BRICS. Step 3: The acronym BRICS stands for Brazil, Russia, India, China and South Africa. Step 4: In the sequence given, Brazil and Russia appear first, followed by a missing country, and then China and South Africa. The missing country must therefore be India to complete the BRICS set in a plausible order. Step 5: Among the answer choices, India is present and matches the required member of the BRICS group.

Verification / Alternative check:
To verify, check whether any of the other options could represent a standard member of the BRICS grouping. Indonesia, Iran and Japan are important countries but are not part of the core BRICS acronym. Only India is historically and currently recognised as one of the original BRIC nations and a member of BRICS. Rewriting the sequence with India inserted gives Brazil, Russia, India, China, South Africa, which matches the well known list. This confirms that India is the only option that completes the pattern correctly.

Why Other Options Are Wrong:
Indonesia, although a major economy, is not part of the BRICS group and therefore does not fit the specific pattern formed by Brazil, Russia, China and South Africa. Iran is also not a BRICS member, and neither is Japan, which is a highly developed economy but not associated with this particular emerging economies group. As the question clearly points to the BRICS pattern, only the country that belongs to this group can be accepted, which rules out these options.

Common Pitfalls:
Some candidates may be tempted to pick a geographically large or economically important country like Japan based on general importance rather than on the precise composition of the BRICS group. Others might confuse BRICS with other groupings such as the G7 or G20. To avoid such mistakes, it is helpful to remember the exact expansion of common acronyms: BRICS stands for Brazil, Russia, India, China and South Africa. Keeping these specific memberships in mind makes questions of this type much easier.

Final Answer:
The missing country in the BRICS sequence is India, so India is the correct answer to complete the series Brazil, Russia, India, China, South Africa.