Examkin

Question

Difficulty: EasyExplicit Causal Relationships

The introduction of the Indo-Pacific lionfish into the Caribbean Sea has precipitated significant ecological disruptions. Unlike native predators, the lionfish possesses venomous spines that deter potential predators and a voracious appetite that rapidly depletes local fish populations. Marine biologists have determined that the most devastating consequence of the lionfish invasion is the dramatic reduction of herbivorous fish species, such as parrotfish. The localized reduction of these herbivores removes the primary natural control on macroalgae growth. Consequently, the unchecked proliferation of macroalgae suffocates the underlying coral reefs, blocking sunlight and preventing new coral polyps from settling, which ultimately leads to the degradation of the entire reef ecosystem.

Based on the passage, what is explicitly stated as the direct cause of the unchecked proliferation of macroalgae on Caribbean coral reefs?

  1. A
    The ability of the macroalgae to block sunlight and prevent new coral polyps from settling
  2. B
    The presence of venomous spines on the lionfish that deter its potential predators
  3. The dramatic reduction of herbivorous fish species that naturally control algae growthAnswer
  4. D
    The complete and permanent extinction of all native marine life in the Caribbean Sea
  5. E
    The increase in water temperatures and agricultural runoff from nearby coastal areas

Answer

The dramatic reduction of herbivorous fish species that naturally control algae growth
The correct answer accurately reflects the direct causal chain provided in the text: the reduction of herbivorous fish removes the natural control on algae, directly leading to its unchecked proliferation.

Step-by-Step Solution

1
Locate the phrase 'unchecked proliferation of macroalgae' within the passage.
The phrase is found in the sentence: 'Consequently, the unchecked proliferation of macroalgae suffocates the underlying coral reefs...'
Finding the specific effect in the text is the first step to tracing back its explicitly stated cause.
2
Read the sentence immediately preceding the located phrase to find the causal link.
The preceding sentence reads: 'The localized reduction of these herbivores removes the primary natural control on macroalgae growth.'
The word 'Consequently' at the start of the final sentence signals that the action in the previous sentence is the direct cause.
3
Identify the core cause from the preceding sentence and match it to the answer choices.
The cause is the reduction of herbivorous fish species, which matches the correct option.
This confirms the explicit causal relationship as stated in the text.

Key Concept

Explicit Causal Relationships
Rate this question

Topics

Explicit Causal Relationships

More questions from this topic