Read the excerpt from The Dark Game: True Spy.
Stories from Invisible Ink to CIA Moles.
Wyke's work was always delicate and demanding,
more so in the damp and confined space. Gently and
carefully, Wyke scraped the dirt until he found the
three cables encased in black rubber and, he
believed, pressurized by nitrogen, a common practice
in the 1950s to keep moisture out of cables. He knew
that once he cut through the rubber sheathing on the
cables, the nitrogen would escape. The resulting drop
in pressure would be detected by the Soviets. The
engineers solved this potential problem by building a
concrete barrier with a steel door to pressurize the tap
chamber and separate it from the pre-amp room. (It
turned out that the cables were not pressurized.)
Wyke next attached wires to the exposed cable-
probably with alligator clips-and began to draw
Mark this and return
Which sentence best states the controlling idea of the
passage?
O Wyke used the technology available in the 1950s
to tap cable.
O Caution and precision enabled Wyke's cable-
tapping success.
Without Wyke, Americans could not have
completed the tunnel.
O Wyke worked to avoid detection by the Soviets in
East Berlin.