Read the text below to answer question.
Spectacular Northern Lights linked to suicidal depression
Alaska's tragically high number of suicide may be
related to cosmic storms and the Northern Lights
(aurora borealis), according to an expert in the study
of brainwaves.
[05] Depression in the Far North has in general been
attributed to the deep, dark and long winters.
But Dr Anita Bush , ________ specialises in
electroencephalography, has complicated matters by
discovering a link between solar flames and brainwave
[10] activity in two sets of Alaskans she has studied for the
past five years.
The microscopic electric impulses were
concentrated in an area of the brain known also to
cause seasonal affective depression (SAD), the
[15] condition up to now blamed for dozens of suicides each
year in the remote Alaskan coast. Suicide levels among
the state's 15 to 24-year-olds have risen sharply in
recent years, to six times the national average, says
Dr Bush.
[20] She has not yet demonstrated a link between
increased brainwaves and suicidal tendencies but she
thinks existing data on supposed SAD cases may in
fact include cases of suicide induced by geomagnetism.
For now she has suggested that special dark glasses,
[25] worn against solar flames and the Northern Lights,
________ elevate morale among the suicidal.
Some of her sceptical colleagues as Professor Tom
Hallinan, one of a team studying the aurora, recently
insisted that the most serious health risk in watching
[30] the Alaskan night sky was a cricked neck.
Adapted from Advance Your English - Cambridge University Press
Mark the option which contains the correct Question Tag of the following sentence.
"She has not yet demonstrated a link between increased brainwaves and suicidal tendencies..."
