The "deep sea" is generally defined as ocean waters below what depth, where sunlight cannot reach?
50 meters
200 meters
500 meters
1000 meters
Which of the following is NOT a major challenge for deep-sea exploration?
Extreme pressure
Total darkness
High temperature
Cold temperatures
What percentage of the deep sea has been explored in detail?
Less than 1%
Approximately 10%
Around 30%
More than 50%
When did humans first reach the deepest part of the ocean (Challenger Deep in the Mariana Trench)?
1945
1960
1985
2000
What percentage of Earth’s surface is covered by the ocean, making its exploration vital for understanding the planet?
51%
61%
71%
81%
Ocean exploration supports global food security by providing protein for how many people worldwide?
1 billion
3 billion
5 billion
7 billion
The ocean acts as Earth’s largest carbon sink（碳汇）. Approximately how much human-caused CO₂ does it absorb annually?
10%
30%
50%
70%
What renewable energy source benefits most from ocean exploration, as it relies on consistent offshore wind speeds?
Solar energy
Offshore wind energy
Geothermal energy
Nuclear energy
The “blue economy” (ocean-related economic activities) is valued at approximately how much annually?
$1 trillion
$5 trillion
$2.5 trillion
$10 trillion
Why is exploring phytoplankton（浮游植物） critical for understanding Earth’s oxygen cycle?
They produce 50% of Earth’s atmospheric oxygen
They consume all of the ocean’s CO₂
They are the main food source for whales
They prevent ocean acidification
How does ocean exploration support developing nations?
By reducing their access to marine resources
By increasing their reliance on terrestrial agriculture
By limiting their coastal tourism
By supporting livelihoods of 60–80 million people (e.g., small-scale fisheries)
Ocean exploration helps address antibiotic resistance（解决抗生素耐药性问题） by studying which marine resource?
Deep-sea bacteria
Coral reefs
Seaweed
Tuna
What is the primary reason ocean exploration is not a “luxury” but a necessity?
It helps humans colonize the ocean
It creates new underwater sports
It increases ocean shipping speeds
It addresses global crises (food scarcity, climate change, resource shortages)
How does ocean exploration help protect biodiversity?
By discovering new species and their habitats to guide conservation
By removing all predators from coral reefs
By increasing ocean temperatures to boost species growth
By reducing ocean salinity