Which one of the following animals is generally known for having the longest natural life span among commonly cited land and marine animals?

Introduction / Context:
Different animal species have very different life spans, ranging from just a few days to well over a century. General knowledge books and school science texts often highlight certain animals that are famous for their long lives. This question asks you to identify which animal is commonly recognised as having one of the longest natural life spans among well known animals, especially in traditional general knowledge context.

Given Data / Assumptions:

• The focus is on animals frequently mentioned in general science or GK sources.
• We are looking for the species with the longest life span among the given options.
• The options list African elephant, Blue whale, Giant tortoise, Horse, and Lion.
• Life span refers to usual maximum natural life span under favourable conditions.

Concept / Approach:
Giant tortoises, especially species from the Galápagos and Seychelles, are famous for their extremely long lives, often exceeding 100 years and sometimes reaching around 150 years or more. Elephants and whales also live long, generally between 60 and 90 years, while horses and lions have much shorter lifespans. In most school level references, the tortoise is highlighted as the animal with the longest life span. The approach is to compare approximate maximum life spans and choose the animal with clearly superior longevity.

Step-by-Step Solution:
Step 1: Recall approximate life spans: horses and lions often live around 15 to 25 years, elephants up to 60 to 70 years, and some whales perhaps a bit longer.Step 2: Remember that giant tortoises are well known for living well past 100 years.Step 3: Compare these ranges and note that the giant tortoise clearly exceeds the typical lifespan of elephants, whales, horses, and lions.Step 4: Also recall that many GK questions and textbooks explicitly state that tortoises have the longest life span among animals commonly discussed.Step 5: Select Giant tortoise as the correct answer.

Verification / Alternative check:
Historical records document individual giant tortoises that have lived more than a century, some reputed to approach 150 to 180 years, though exact ages can be difficult to confirm. Scientific literature agrees that these tortoises are among the longest lived vertebrates. While some whales may also reach great ages, in typical school level general knowledge the tortoise is consistently cited as the longest lived animal, validating this choice in the context of such exams.

Why Other Options Are Wrong:
Option A: African elephants do live long, but their maximum life span is usually significantly less than giant tortoises.Option B: Blue whales are long lived marine mammals, but in standard GK references they are not usually presented as the longest lived animals compared to tortoises.Option D: Horses typically live around 20 to 30 years at best.Option E: Lions in the wild live even shorter lives, often around 10 to 15 years.

Common Pitfalls:
Students may be tempted to choose elephants or whales simply because they are large and famous. Another pitfall is ignoring the difference between average life span and exceptional maximum life span. To avoid confusion, remember that giant tortoises have long been iconic examples of extreme longevity and are frequently named in exam oriented material as the animals with the longest life span.

Final Answer:
The correct answer is Giant tortoise.