Why we need to dup things in define_method blocks

gistfile1.rb

class Obj
  def self.new_method(name, options = {})
    define_method(name) { options }
  end
end

o = Obj.new

options = { one: :two }
Obj.new_method('baz', options)
o.baz # =>{:one=>:two}

options[:asgfasdgsadg] = :sdagsadg
o.baz # => {:one=>:two, :asgfasdgsadg=>:sdagsadg}