That is partly _____29_____ a drop-off in investment created by the decline in oil prices in the '90s. But it is also because multinational corporations like Exxon Mobil (despite its record profits) now own just six percent of supplies, _____30_____ a whopping 77 percent that's now owned by state-owned entities, _____31_____ the Petroleum Finance Corp., a Washington-based consulting group.
【題組】30. (A). according to (B). because of (C). unlike (D). versus