Which of the following birds is known for its very slow breeding cycle and typically lays only one egg in about two years?

Introduction / Context:
This zoology question highlights a bird with an unusually slow breeding cycle. Some large seabirds invest so much energy in rearing their young that they breed only once every one or two years. Knowing which bird lays just a single egg in such a long period demonstrates understanding of life history strategies and typical exam facts from animal world general knowledge.

Given Data / Assumptions:

• The question is about a bird with a very low reproductive rate.
• It specifies that the bird typically lays one egg in about two years.
• The options list large or notable birds such as albatross, kiwi, ostrich, penguin and emu.
• We assume the question reflects common general knowledge wording used in many competitive exam books.

Concept / Approach:
Albatrosses are large oceanic birds known for their long lifespan, delayed maturity and slow reproduction. Many species form long lasting pairs and lay only one egg per breeding attempt, with breeding intervals that can be about two years because parents invest extensive time in incubation and chick rearing. Birds like ostrich and emu lay multiple eggs in a season, while penguins and kiwis, although laying one or two eggs, usually breed annually, not once every two years as a standard pattern in simple exam facts.

Step-by-Step Solution:
Step 1: Identify which of the listed birds are long lived seabirds with slow reproductive cycles. Step 2: Recall that albatrosses have lengthy incubation and chick rearing periods and therefore cannot breed every year easily. Step 3: Compare this with ostrich and emu, which lay many eggs on land and can breed more frequently. Step 4: Note that penguins and kiwis typically follow an annual breeding cycle rather than consistently skipping a year. Step 5: Conclude that the description of a bird laying only one egg in two years best matches the generalised exam description for albatross.

Verification / Alternative check:
In many general knowledge and biology question banks, you will find a direct question stating that the bird which lays one egg in two years is the albatross. These references often use this fact to emphasise the slow breeding and vulnerability of large seabirds. While real life breeding intervals may vary slightly between species, exam oriented material consistently links this statement with albatross, which supports the selection of this answer.

Why Other Options Are Wrong:
Kiwi lays a very large egg relative to its body size but generally breeds annually, not only once in two years as a common rule in exam facts.
Ostrich lays a clutch of many eggs in one season and has a higher reproductive rate than the question suggests.
Penguin species typically lay one or two eggs each breeding season, with most species attempting to breed every year.
Emu also lays multiple eggs over a season, and its breeding interval is not as slow as one egg in two years.

Common Pitfalls:
Students sometimes overanalyse biological details or recall that other birds also lay a small number of eggs and then become unsure. Another pitfall is confusing largest egg or heaviest egg with slowest breeding interval. To avoid confusion, remember that the standard exam association is: albatross equals very slow breeding and one egg in about two years, while ostrich equals largest living bird and kiwi equals largest egg relative to body size.

Final Answer:
The bird known for laying only one egg in about two years is the albatross.